The present disclosure relates to a ring-type network connected through an Ethernet port, and more particularly, enables the ring-type network to be linked to other networks having various topologies while maintaining an original ring structure.
Recently, expandability has come to the fore as an important element in an industrial network due to a highly industrialized society, massive information, and high complexity, and the industrial network needs to support topologies having various shapes so as to integrate and manage distributed sites.
In particular, a ring topology network holds a place as an important axis in the industrial network so that international protocol (such as IEC 62439) establishes a protocol for a ring topology based industrial network.
The ring topology network has an advantage in that the reliability of a network may be secured because even if an intermediate node has an error, the ring topology network may communicate through other paths.
In general, industrial sites enhance network performance by connecting several communication devices (nodes) having two Ethernet ports through Ethernet to form a ring topology network.
FIG. 1 shows a node 10 having two Ethernet ports. Port #1 and port #2 are used for configuring a ring topology network.
FIG. 2 shows an example of a ring topology network using several nodes having two Ethernet ports. A second port P11 of node #11 and a first port P12 of node #12, a second port P13 of node #12 and a first port P14 of node #13, a second port p15 of node #13 and a first port P16 of node #14, a second port P17 of node #14 and a first port P18 of node #15, and a second port P19 of node #15 and a first port P20 of node #11 are sequentially connected to form a ring topology network.
However, such a typical method of configuring a ring topology network has a drawback in that the expandability of a network decreases because the method is just interested in connecting nodes in a ring shape.
For example, since the number of Ethernet ports of a node that supports a ring topology network is limited to two, it is difficult to configure networks in various shapes.
Moreover, once a ring topology network is configured, linking to a network other than a corresponding ring topology network is not considered and it is difficult to integrate and manage several networks previously built as a single network.